Electric oil pan heating device



Juiy 11, 1967 J, 5, WELLS 3,339,935

ELECTRIC OIL PAN HEATING DEVICE Filed April 7, 1965 INVENTOR. Joe 5. Wells BY 1 wag; g ATTORNEYS United States Patent 3,330,935 ELECTRIC OIL PAN HEATING DEVICE Joe S. Wells, 1120 Clinton Way, Colorado Springs, Colo. 80907 Filed Apr. 7, 1965, Ser. No. 446,264 3 Claims. (Cl. 219-205) This invention relates to heaters for mounting on the exterior of the oil pan of an internal combustion engine.

In northern latitudes where the temperatures fall below the congealing point of oil, it is almost imperative that vehicles left outside in the elements have some sort of heating arrangement to either maintain the oil fluid or quickly heat it until it is fluid to permit the engine to be started. Numerous heaters have been suggested in the prior art, including electric dip stick heaters, electric head bolt heaters and various types of oil pan heaters. Some of the oil pan heaters of the prior art require modification of the pan, as by drilling bolt holes or the like in the pan, some have the electrical connectors in a generally unaccessible spot which is also subject to corrosion, some are simply too elaborate for easy installation and maintenance, and most are impractical as too small or provide insufiicient heat.

According to the present invention, I have provided a simplified heater for the oil pan of an internal combustion engine which is simply mounted and is maintained in intimate contact with the exterior of the oil pan, and is easily and quickly removed when the heater is not necessary. In addition, the heater provides suflicient heat for extreme temperatures in a high and low range for quick heating or long term slow heating, respectively, depending on the use desired. Of considerable importance is the fact that, the heater of the invention is arranged for easy and quick attachment to substantially any internal combustion engines of automobiles, the engines of tractors, prime movers and the like. It is useful in disel engines as well as gasoline engines. The heater may be fitted to an engine without modification of the engine and it will be held in tight contact with the oil pan or other desired location of the engine.

Included among the objects and advantages of the present invention is a simplified high capacity heater for the oil pan of an internal combustion engine. The device is arranged for simple and easy attachment without modification of an internal combustion engine. The heater includes two heating elements which are arranged for use of one or two at a time for low and high ranges. The device is arranged to be mounted by means of springs which maintain the heater in tight surface contact with the exterior of the oil pan of an internal combustion engine.

These and other objects and advantages of the invention may be readily ascertained by referring to the following description and illustrations in which:

FIG. 1 is a perspective view of a portion of an automobile including an automobile engine with the heater of the invention mounted thereon;

FIG. 2 is a top plan view of the heater according to the invention with the mounting attachments thereon;

FIG. 3 is a side elevational view of a holding bracket for the mounting arrangement of the heater; and

FIG. 4 is a wiring diagram of one form of heater according to the invention.

In the device selected for illustration, a pair of metal sheathed, tubular resistance type heaters are bent in a reverse curve and mounted one inside the other in the same plane for attachment to the oil pan of the vehicle. As shown in FIG. 2, one heater element is formed generally circular with the ends 11 and 12 extending outwardly beyond the curved portion and an inner heating element 15 is formed on a generally circular smaller diameter than the element 10 and its ends 16 and 17 extend beyond its curve in the same direction as the ends 11 and 12. The ends are mounted in a cap 18 to which is also mounted a lead cable 20, which is a multiple wire lead connected to the resistors of the heating elements as explained below. The ends are held in the cap 18 by means of a potting compound, not shown, which is preferably a thermo setting potting compound, several types of which are commercially available, to securely hold the ends in the cap 18.

The elements 10 and 15 are preferably of the metal sheath, resistance type heaters which are generally filled with a mineral, for example, titanium dioxide. The heating elements 10 and 15 are mounted in the same plane and both are spot welded to a reflector ring 22, which is a flat piece of metal, preferably stainless steel, which provides a framework for holding the heating elements in the same plane and to reflect heat from the heating elements upwardly unidirectionally. The conductor cable 20 extends from the cap 18 to an end fixture 23, which includes a high-low switch 24 and, in one form, a two prong outlet plug 25 arranged to telescope in a female two prong plug. Obviously, the two prong plug may be replaced with a conventional three prong plug.

The heating elements are preferably slender, being not more than of an inch in diameter. The length should be sufiicient so that the exterior element has about a 6- inch diameter. With this length, the interior element 15 singly should produce about 150 watts at volts stand ard house current and the exterior element 10 should produce about 200 watts. The total with both elements operating is about 350 watts.

The heater is attached to an automobile engine by means of spring supports, and the springs are held to the heater by means of strap metal clamps or heater tabs 30, shown in FIG. 3, each of which includes a hook member 31 that hooks into the reflector material 22 underneath the inside heating element 15 and extends outwardly therebeyond. Each tab is provided with an aperture 33 at its outer end. A long shank helical spring 35 is aflixed in the apertures 33 by means of a ring portion 36 on the end of the spring. A bolt clamp or bolt tab 37 having an aperture 38 therein is secured to the other end of each spring by means of a ring portion 39 on the other end of the spring. The bolt clamp 37 includes an enlarged opening 40 with a slot 41 extending from the edge into the opening 40. This provides means for attaching the clamp to a bolt without actually removing the bolt from the engine.

The heater is simply attached to the pan 50 of an automobile engine 51, shown in FIG. 1, by means of the bolt tabs 37, the springs and heater clamps 30. For attaching the bolt tab, one oil pan bolt is loosened on each side of the oil pan directly above the oil sump. One of the slotted metal tabs 37 is then inserted over each loosened bolt with a twisting motion and inserting the slot around the bolt. When the tab is around the bolt, the bolt is retightened. The spring is then attached to the bolt tab 37 at one end. The long shank of the spring may be pulled through the opening 33 of the heater tab, pulled around and bent around itself to form an eye or ring, the springs being stretched approximately 3 inches after the heater tabs are secured on the reflector so that the heater is held securely against the oil pan. The heater elements are placed directly in contact With the oil pan with the reflector on the bottom. The cord 20 is pulled up to an accessible part, as through the grill of the automobile as shown in FIG. 1. Where pan bolts are not accessible, the springs may be attached to any spot on the engine where suflicient tension may be placed on the springs to pull the heater closely to the pan.

The wiring diagram of FIG. 4 shows essentially one form of circuitry for a two position switch. The outer heat element 10 is connected by its end 11 to a ground 3 lead 55 and the opposite end 12 is connected to a hot lead 56 which terminates at a contact 67. The end 16 of the inner heat element is connected to another ground lead 57 and the opposite end 17 is connected to a hot lead 58 which terminates at contact 66. The two grounds 55 and 57 are joined at a junction 59. Where necessary or desired, a third ground wire 60 may be attached to the junction 59 or to metal of the unit for grounding the device. A switch 63 is mounted in a fixture 23 which is provided with the prongs 25 for attachment to a female plug. The switch includes a contact rocker arm 65 which is always in contact with contact 66 and is in contact with contact 67 when depressed. Such switches are common on the market and do not form a part of the invention per se. In the switch form shown, the inner member is always in the circuit and the low position indicates this condition. When the rocker 65 is depressed, it contacts both the contacts 66 and 67 to put both of the heating elements in the circuit, thus activating both elements. When the third wire is used, the plug is a conventional three prong plug.

For operation after the heater is attached to the automobile with the elements in tight contact with the oil pan, an extension cord is connected to the fixture 23 by means of the prongs 25. For slow, long term heating as overnight the switch is placed in the low position. This produces about 150 watts of heat and by the long term heating the entire engine is heated from the bottom up by radiation. For a quicker warm-up, the switch is turned to high, by depressing rocker 63 so that both elements are activated, producing about 350 watts of heat. In the summer or warmer periods when the heater is not needed, it may be easily removed by disconnecting the spring from the bolt tab 37 on both sides and removing the cord from the grill. The heater is then easily attached by merely reattaching the springs to the bolt tab positioning the heater against the oil pan.

While the invention has been illustrated by reference to a specific device, there is no intent to limit the spirit or scope of the invention to precise details so set forth except as defined in the following claims.

I claim:

1. A heating device for the removable attachment to the exterior of an oil pan of an internal combustion engine comprising a metal reflector plate being strong enough to support itself and provided with a central aperture; a pair of metal sheathed, resistance type heating elements lying in the same plane adjacent to one another and welded to said reflector plate; a conductor secured to each end of said resistance type heater and extended to switch means; the ends of the heaters being enclosed in a metal cap and sealed therein by potting compound; said switch means being at least a two way switch arranged to separately activate one said heater in one position and both said heaters in another position; a pair of strap metal clips gripping said reflector plate through said central aperture and extending outwardly beyond said reflector plate, there being an opening in the outer extremity of each of said clips; elongated spring means secured to each said clip and extending therebeyond; means for securing said spring means to opposite sides of an engine so as to maintain said heaters firmly against the exterior of the oil pan of said engine; and means for connecting said switch means to an extension cord.

2. A heating device for the removable attachment to the exterior of an oil pan of an internal combustion engine comprising a metal reflector plate being strong enough to support itself and provided with a central aperture; a pair of metal sheathed, resistance type heating elements lying in the same plane adjacent to one another and welded to said reflector plate; a conductor secured to each end of said resistance type heater and extended to switch means; the ends of the heaters being enclosed in a metal cap and sealed therein by potting compound; said switch means being at least a two way switch arranged to separately activate one said heater in one position and both said heaters in another position; a pair of strap metal clips gripping said reflector plate through said central aperture and extending outwardly beyond said reflector plate, there being an opening in the outer extremity of each of said clips; spring means having an elongated shank secured to each said clip and extending therebeyond; means for securing one end of each said spring means to an engine bolt on opposite sides of said engine so as to maintain said heaters firmly against the exterior of the oil pan of said engine; and means for connecting said switch means to an extension cord.

3. A heating device for the removable attachment to the exterior of an oil pan of an internal combustion engine comprising a metal reflector plate being strong enough to support itself and provided with a central aperture; a pair of metal sheathed, resistance type heating elements lying in the same plane adjacent to one another and welded to said reflector plate; a conductor secured to each end of said resistance type heater and extended to switch means; the ends of the heaters being enclosed in a metal cap and sealed therein by potting compound; said switch means being at least a two way switch arranged to separately activate one said heater in one position and both said heaters in another position; a pair of strap metal clips gripping said reflector plate through said central aperture and extending outwardly beyond said refiector plate, there being an opening in the outer extremity of each of said clips; a helical spring having a long shank secured to each said clip and extending therebeyond; slotted bolt tab means for securing said springs to an engine bolt on opposite sides of an engine so as to maintain said heaters firmly against the exterior of the oil pan of said engine; and means for connecting said switch means to an extension cord.

References Cited UNITED STATES PATENTS 1,645,230 10/1927 Corlew et al 219526 1,764,021 6/1930 Jackson 219205 1,999,003 4/1935 Bushnell 219205 2,361,874 10/1944 Russell 2l9461 X 2,370,767 3/1945 Backer 219447 2,677,040 4/ 1954 Byron 2l9205 2,702,335 2/1955 Cordis 219205 X ANTHONY BARTIS, Primary Examiner. 

1. A HEATING DEVICE FOR THE REMOVABLE ATTACHMENT TO THE EXTERIOR OF AN OIL PAN OF AN INTERNAL COMBUSTION ENGINE COMPRISING A METAL REFLECTOR PLATE BEING STRONG ENOUGH TO SUPPORT ITSELF AND PROVIDED WITH A CENTRAL APERTURE; A PAIR OF METAL SHEATHED, RESISTANCE TYPE HEATING ELEMENTS LYING IN THE SAME PLANE ADJACENT TO ONE ANOTHER AND WELDED TO SAID REFLECTOR PLATE; A CONDUCTOR SECURED TO EACH END OF SAID RESISTANCE TYPE HEATER AND EXTENDED TO SWITCH MEANS; THE ENDS OF THE HEATERS BEING ENCLOSED IN A METAL CAP AND SEALED THEREIN BY POTTING COMPOUND; SAID SWITCH MEANS BEING AT LEAST TWO WAY SWITCH ARRANGED TO SEPARATELY ACTIVATE ONE SAID HEATER IN ONE POSITION AND BOTH SAID HEATERS IN ANOTHER POSITION; A PAIR OF STRAP METAL CLIPS GRIPPING SAID REFLECTOR PLATE THROUGH SAID CENTRAL APERTURE AND EXTENDING OUTWARDLY BEYOND SAID REFLECTOR PLATE, THERE BEING AN OPENING IN THE OUTER EXTREMITY OF EACH OF SAID CLIPS; ELONGATED SPRING MEANS SECURED TO EACH SAID CLIP AND EXTENDING THEREBEYOND; MEANS FOR SECURING SAID SPRING MEANS TO OPPOSITE SIDES OF AN ENGINE SO AS TO MAINTAIN SAID HEATERS FIRMLY AGAINST THE EXTERIOR OF THE OIL PAN OF SAID ENGINE; AND MEANS FOR CONNECTING SAID SWITCH MEANS TO AN EXTENSION CORD. 